Efficacy of infliximab in a patient with refractory idiopathic retroperitoneal fibrosis

Glucocorticoids are the mainstay of treatment of idiopathic retroperitoneal fibrosis (IRF). However, relapses are frequent upon tapering of the glucocorticoid dose. A variety of traditional immunosuppressants have been proposed as steroid-sparing agents, but some patients fail to adequately respond to combined glucocorticoid and immunosuppressive therapy. We report a patient with IRF refractory to combined glucocorticoid and methotrexate therapy treated with the anti-TNF-α monoclonal antibody infliximab. Infliximab was administered at 5 mglkglbodyweight at week 0,2, 6 and 8-weekly thereafter for 3 consecutive years. Drug efficacy and safety were assessed clinically and by laboratory tests at treatment onset and subsequently before each infusion. In addition, ¹⁸F-Fluorodeoxyglucose (FDG) positron emission computerised tomography (PET/CT) and abdominal CT scans were used to monitor disease activity and response to treatment. Infliximab therapy resulted in a satisfactory clinical and laboratory response paralleled by an improvement in imaging findings. No serious adverse events were noted. Infliximab may be an effective and safe treatment for refractory IRF. A controlled study is required to confirm our findings.